textproduct: Quad Cities

KEY MESSAGES

- Frost Advisory in effect across the north for tonight with lows in the mid/upper 30s anticipated.

- A clipper-like system late Monday night into Tuesday morning is forecast to bring scattered (30-60%) showers and thunderstorms to the region.

- Warm up expected late week with temperatures reaching into the 80s by Friday as the next storm system approaches.

SHORT TERM /THROUGH TONIGHT/

Issued at 200 PM CDT Sun May 10 2026

A broad area of high pressure will remain over the Upper Mississippi Valley region through tonight, with an upper level trough axis expected to shift to the east through the Great Lakes. A dry air mass in place with dewpoints in the 30s and 20s, combined with periods of clear skies, will allow temperatures to drop into the 40s and 30s for lows tonight. The coldest temperatures are expected in the counties along the Highway 20 corridor, where mid 30s are possible. Confidence remains low on potential for widespread frost due to the expectation for marginally cool temps in the mid/upper 30s and potential for NE winds to hold around 10 mph at times through the overnight. However, decided to issue a Frost Advisory for the northern tier of counties where lows in the mid 30s are most likely. Temperatures early this morning were several degrees below most model guidance, so potential is there for a repeat scenario again tonight given the dry air mass; went a few degrees below the latest NBM for lows with mid/upper 30s north and low to mid 40s roughly I-80 and south.

LONG TERM /MONDAY THROUGH SATURDAY/

Issued at 200 PM CDT Sun May 10 2026

Monday...As the longwave trough over the Great Lakes and high pressure over Wisconsin slide to the east, ridging builds in over the CWA. Large-scale subsidence on Monday will provide mostly sunny skies with highs in the 60s north of I-80 and 70s south. This is not expected to last long as a developing 850-700 mb f-gen band will push clouds in from north Monday night.

Tuesday...A clipper-like system over northern Minnesota is forecasted to propagate into Wisconsin as the next shortwave trough in south-central Canada dives into the Northern Plains. A band of light stratiform rain will develop across northeast Iowa and northern Illinois associated with the f-gen previously mentioned. Dry air in the low levels should limit overall QPF. Regardless of precipitation though, winds will be gusty Tuesday afternoon as the cold front moves through the region with gusts between 30 to 40 mph possible as southwesterly flow gradually turns to the west/northwest. Skies should clear out Tuesday night as CAA and ageostrophic convergence aloft on the backside of the passing trough sets in.

Wednesday through Thursday afternoon...Another longwave ridge builds in from the west Wednesday and a high pressure anchors to our north. Highs will be seasonable in the mid-60s to mid-70s with light northerly winds. Things start to shake up on Thursday when the next trough over the northern Rockies kicks the high pressure to the east, shifting the winds to southerly once again.

Thursday night through Saturday...The trough over the northern Rockies moves into the Northern Plains, deepening a low pressure center over Dakotas Thursday night. This strengthens the 1000-700 mb mean flow to 20-30 knots out of the south- southwest which advects in much needed moisture into the region with PWATs increasing over 0.5 inch overnight Thursday. The approaching cold front will be the focal point of convection Friday. While it is too far out to determine the severity of these storms, the latest ENS run shows a 20-50% chance of MUCAPE exceeding 1000 J/kg across the CWA.

The cold front swings through Friday night into Saturday morning as the shortwave becomes negatively tilted over the Upper Mississippi River Valley. Dry and cold air advection will clear out the precipitation from west to east, but the exact timing is uncertain as there is disagreement among the GEFS and ENS members on the propagation speed and track of this low pressure system. Nevertheless, highs in 80s on Friday are becoming increasingly likely while Saturday will be dependent on the timing of the front.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1159 AM CDT Sun May 10 2026

VFR to continue with steady NW winds through this afternoon, decreasing to 5-10 kts and turning to the N/NE tonight into Monday AM.

DVN WATCHES/WARNINGS/ADVISORIES

IA...Frost Advisory from 2 AM to 8 AM CDT Monday for IAZ040>042. IL...Frost Advisory from 2 AM to 8 AM CDT Monday for ILZ001-002. MO...None.